IPSec tunnel mode

In winhec 2005 it was published that tunnel mode offload will not be
supported on NDIS 6.0 IPsec Task Offload. Thus even if the miniport
advertises the capability, it will not be used. Is it still true in vista
beta and will it be true in final version?
Also was wondering why this feature was taken out when it was supported in
NDIS 5.x?